Collie Health Guide
The iconic herding breed with critical medication sensitivities—MDR1 affects 70% of Collies, making common drugs potentially fatal.
12-14
Years Lifespan
50-75
Pounds
~70%
MDR1 Affected
#38
AKC Popularity
Critical: MDR1 Testing is Essential
About 70% of Collies have the MDR1 mutation—the highest rate of any breed. Common medications like Imodium (available over the counter!) can be fatal. Get your Collie DNA tested immediately if not already done, and always inform every vet before any treatment.
The Collie Health Profile
Both Rough and Smooth Collies share the same health concerns. While generally healthy, they have specific genetic vulnerabilities that require attention:
- MDR1 drug sensitivity: Highest rate of any breed—testing is non-negotiable
- Collie Eye Anomaly: Up to 90% affected in some populations
- Dermatomyositis: Inflammatory skin/muscle disease in young dogs
- Epilepsy: Elevated rates—medication choice affected by MDR1
Major Health Conditions
1. MDR1 Drug Sensitivity
~70% of ColliesThe MDR1 gene mutation prevents the blood-brain barrier from blocking certain drugs. This means medications that are safe for other dogs can accumulate in the brain of affected Collies, causing severe neurological reactions or death.
Dangerous Medications for MDR1 Dogs:
- • Ivermectin (some heartworm preventatives, deworming)
- • Loperamide (Imodium) — over the counter and DEADLY
- • Acepromazine (common sedative)
- • Butorphanol (pain medication)
- • Some chemotherapy drugs (vincristine, doxorubicin)
- • Some antibiotics at high doses
Reaction signs:
- • Disorientation, stumbling
- • Excessive drooling
- • Tremors
- • Blindness
- • Seizures, coma, death
What to do:
- • Get DNA test immediately
- • Inform ALL vets of MDR1 status
- • Use MDR1-safe heartworm prevention
- • Never give Imodium
- • Carry a card/tag with MDR1 status
Safe Heartworm Prevention Options:
Heartgard (ivermectin at preventative doses is safe), Sentinel, Interceptor, and Revolution are generally safe for MDR1 dogs at normal doses. Always confirm with your vet.
2. Collie Eye Anomaly (CEA)
Up to 90% affectedCEA is a developmental defect affecting the back of the eye. Severity ranges from mild (no vision impact) to severe (blindness from retinal detachment). It's present from birth and doesn't progress.
What to know:
- • Most affected dogs have mild form
- • Vision often remains functional
- • Can cause retinal detachment (severe)
- • Present from birth, doesn't worsen
- • DNA test identifies carriers
Prevention:
- • Eye exam before 8 weeks (best visibility)
- • DNA test for breeding dogs
- • Buy from tested parents
- • Ask breeder for CAER results
3. Dermatomyositis (DM)
Breed predisposedAn inflammatory disease affecting skin and muscles, primarily in Collies and Shelties. Usually appears in puppies under 6 months but can occur in adults. Triggered by genetics plus environmental factors.
Signs:
- • Skin lesions on face, ears, legs, tail tip
- • Hair loss in affected areas
- • Scarring, crusting
- • Muscle weakness (severe cases)
- • Difficulty swallowing (severe)
Treatment:
- • Avoid sun exposure (worsens it)
- • Omega fatty acids
- • Vitamin E supplementation
- • Immunosuppressants if severe
- • Many dogs have mild, manageable cases
4. Epilepsy
Elevated riskCollies have elevated rates of idiopathic epilepsy. Important: MDR1 status affects which medications are safe for seizure control.
Seizure signs:
- • Collapse, stiffening
- • Paddling legs
- • Loss of consciousness
- • Drooling, loss of bladder
- • Confusion afterward
Management:
- • Tell vet about MDR1 status!
- • Phenobarbital, levetiracetam usually safe
- • Keep seizure diary
- • Regular blood monitoring
- • Most live normal lives
5. Gray Collie Syndrome (Cyclic Neutropenia)
Rare but seriousA rare inherited condition where the immune system cycles between normal and severely compromised every 10-12 days. Affected puppies have a distinctive silver-gray coat color.
Signs:
- • Silver-gray dilute coat color
- • Recurrent infections
- • Fever episodes
- • Poor growth
- • Usually fatal in first 2 years
Prevention:
- • DNA test available for carriers
- • Responsible breeders test
- • Avoid breeding carriers together
Essential Care for Collies
Priority Health Steps
Non-negotiable—do immediately
For CEA screening
Every visit, every vet
Even if MDR1 normal—play it safe
Emergency Signs:
- Drug reaction (stumbling, tremors, drooling after any medication)
- Seizure lasting more than 5 minutes
- Sudden vision loss or eye pain
- Difficulty swallowing or severe muscle weakness
- Any unusual behavior after medication
Understand Your Collie's Health Better
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Upload Your Dog's Records FreeFrequently Asked Questions
What is the lifespan of a Collie?
Collies typically live 12-14 years. Both Rough and Smooth Collies share the same health concerns. MDR1 drug sensitivity affects about 70%—the highest rate of any breed.
What is MDR1 drug sensitivity?
About 70% of Collies have the MDR1 mutation, causing potentially fatal reactions to common medications including ivermectin and Imodium. DNA testing is essential for all Collies.
What medications are dangerous for Collies?
Avoid ivermectin (some heartworm preventatives), loperamide (Imodium), acepromazine, butorphanol, and certain chemo drugs. Always inform your vet you have a Collie.
What is Collie Eye Anomaly (CEA)?
CEA affects up to 90% of Collies in some populations. It ranges from mild (no vision impact) to severe (blindness). DNA testing can identify carriers. Eye exams should be done before 8 weeks.
What is dermatomyositis in Collies?
DM is an inflammatory disease affecting skin and muscles, usually appearing in puppies under 6 months. Signs include skin lesions on the face and ears. Many cases are mild and manageable.
Do Collies get epilepsy?
Yes, Collies have elevated epilepsy rates. Important: MDR1 status affects which medications are safe for seizure control, so always mention your Collie's MDR1 results.